The traditional concept of God, rooted in the biblical and patristic witness, is that God exist uniquely a se. That is to say, God is the only self-existent being, the sole ultimate reality, and all else that exists has been created by God. The most important challenge to this doctrine issues from Platonism, the view that there exist necessary, eternal, uncreated abstract objects. The main argument for Platonism is the so-called Indispensability Argument, which holds that our use of first-order logical quantifiers and singular terms in sentences we take to be true commits us ontologically to the reality of such objects. Theists might attempt to escape this challenge by adopting anti-Platonic forms of realism about such objects. But an arguably better course is to challenge the devices of ontological commitment which underlie the Indispensability Argument. When called upon to speak about such objects in a metaphysically heavy sense, the theist should regard such objects no more than useful fictions.